They are a superior/more reliable motor than the full crank, but they have greater issues once they have been straight fueled. The advantage of the full crank for me is that if a motor has been straight fueled, I can swap over a good barrel and piston, give it a hone, new set of rings and away it goes again. Makes it easy when you have a lot of motors to mix and match with and time no longer means anything to you any more
